19th century Louisiana is the setting for Duel on the Mississippi. Patricia Medina stars as Lili Scarlet, a vengeful Creole girl who masterminds a series of pirate raids on the local plantations. To cover up her perfidy, Lili operates a lavish gambling ship, and it is here that aristocratic Jules Tulane (John Dehner) runs up a huge debt. As "security", Jules' son Andre (Lex Barker) turns himself over to Lili as a sort of bond slave. It doesn't take long for Andre and Lili to fall in love, much to the dismay of her knife-wielding paramour Hugo Marat (Warren Stevens). The titular duel between Andre and Hugo, fought with machetes, is the film's most exciting sequence. ~ Hal Erickson, Rovi